Mast hoist



May 26, 1925. 1,539,344

R. M. ADAM MAST HOIST Filed June 21, 1923 2 Sheets-Sheet 1 R.M.ADAM

' May 26, 1925.

MAST HOIST 2 Sheets-Sheet 2 Filed June 21, 1923 Invento Robe zM/idam,

Patented May 26, 1925.

i v UNITED STATES PATENT OFFICE.

ROBERT 'M. ADAM, "0F PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO JOHN H. V MCCLA'I'CHY, OF II-IILAI'JELPHIA, PENNSYLVANIA. i i

. MAST nors'r.

Application filed June 21, 1923. Serial No. 646,751.

To all whom it may concern: 7

Be it known that I, ROBERT M. ADAM, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Mast Hoists, of which I declare the following to be a full, clear, and'exact description.

My invention relates to improvements in mast hoists and has to do, more particular- 1y, with hoists or elevators for use in connection with building operations.

The principal object of my invention is to provide a mast hoist which is very cheap, simple andcompact in construction, requires very few guys or braces, and can be quickly and easily erected or taken down and moved from one job to another.

A further object of my. invention is to provide hoisting apparatus which can be adjusted very quickly and easily for lifting to different heights.

A further object of my invention is to provide a mast hoist in which the stresses and forces acting on the hoist tend to balance each other so that the resultant forces tending to deflect the mast from the vertical are reduced to a minimum.

Further objects, and objects relating to details and economies of operation and con; struction, will definitely appear from the detailed description to follow. In one instance, I accomplish the objects of my in vention by the devices and means set forth in the following specification. My inven tion is clearly defined and pointed out in the appended claims. A structure constituting a preferred embodiment of my invention is illustrated in the accompanying drawings, forming a part of this specification, in which:

Fig. 1 is a view in side elevation of a hoist embodying my invention.

Fig. 2 is a view of the hoist in front elevation looking from a point between the mast and the hoisting engine.

Fig. 8 is an enlarged view of a portion of the mast in front elevation, showing the platforms as they are about to pass each other, the side of one of the channel tracks being broken away to show the platformsupporting rollers, and t it Fig. 1 is a transverse, sectional view taken on the line t4c ofFig. 3 and showing the lifting platforms in bottom plan view.

In the drawings, the same reference nu merals refer to the same parts throughout the several views and thesectional viewis taken looking in the direction of the arrows at the ends of the section line.

Referring to the numbered parts of the drawings, the vertical mast, 11,is stiffened and strengthened by the channel tracks, 15,

base of the mast hoist. The upper portion of the mast may also be braced by braces, 13, fastened to the joists, 1 1, of the building or other structure in connection with which the hoist is used. At the top of the mast, a cross bar, 18, is fastened and braced by braces, 19,

, and the pulleys, 20, are journaled at the ends of this cross bar.

The tracks, 15, are of channel cross-section and the outer portions ofthe channel side walls are/bent inwardly forming the guideways, 17, with an entrance slot between them. Each of the two lifting platforms, 21, consists of the floor, 25, supported by the bars, 22, and braces, 23, which are connected to the upright formed by the vertical channelbar, 24:, extending at one side of the platform, with a channel opening toward the platform. This channel bar extends above and below the platform and the brackets, 26, are fastened to the base of said channel bar and pass through the entrance slot between the guideways, 17 into the channel-shaped track, 15. The rollers, 27,

are journaled on the brackets, 26, and cooperate with the track, 15. In the present instance, there are four of these rollers journaled on each bracket, the rollers being arranged in pairs with a pair of rollers in line with each of the guideways, 17. In the hoisting apparatus illustrated, there are two of these brackets, 26, fastened to each. channel bar, 24, and one of these brackets is located above. the platform, 21, while the other is located below the platform. The result is that the weight of the platform, and the load carried by it,forces therollers till slot between them, a lifting platform, a bracket carried by said platform and extending through said entrance slot into the channel, rollers carried by said bracket in line with said guideways, a hoisting cable connected to said platform, and means for actuating said cable.

4. An apparatus of the class described comprising a mast, a channel fastened to the side of the mast and forming a track, the sidewalls of said channel being bent inwardly forming outer guideways with an entrance slot between them, a lifting platform,

an upright connected thereto, brackets car-V ried by said upright and extending through said entrance slot into the channel, rollers carried by said brackets in line with the guideways, and adapted to roll upon either said guidewa-ys or the base of said channel, a hoisting cable connected to said platform, and means for actuating said cable.

5. An apparatus of the class described comprising a mast, a channel forming a track and having its base abutting and se cured to the side of said mast, the side walls of said channel being bent inwardly forming outer guideways with an entrance slot between them, a lifting platform including a floor and an upright connected thereto and extending above and below said floor, a pair of brackets carried by said upright and extending through said entrance slot into the channel, one of said brackets being located above and the other below the level of the floor, rollers carried by said brackets in line with said guideways and adapted to roll either upon said guideways or the base of the channel, a hoisting cable connected to said upright, and means for actuating said cable.

6. An apparatus of the class described comprising a mast, a cross bar secured to the top of the mast, pulleys journaled at the ends of said cross bar, channels fastened to opposite sides of the mast and forming tracks, adapted to take thrust-in two opposite direc tions lifting platforms provided with guide means working in said channels, a hoisting cable having its ends fastened to said platforms and passing over said pulleys, and means for actuating said cable.

7. An apparatus of the class described comprising a mast, a pair of upper pulleys mounted at the top of said mast, a pair of lower pulleys mounted at the foot of said mast, channels fastened to opposite sides of said mast and forming tracks, adapted to take thrust in two opposite directions lifting platforms provided with a guide means working in said channels, a rotatable hoisting drum, and a hoisting cable having its ends fastened to said platforms, passing therefrom up and around the upper pulleys,

thence down and around the lower pulleys and thence around the drum.

. 8. An apparatus of the class described comprising a mast, a pair of upper pulleys at the top of the mast, a pair of lower pulleys at the foot of the mast, channels fastened to the opposite sides of said mast and forming tracks, the sides of said channels being bent inwardly forming outer guideways with an entrance slot between them, a

pair of lifting platforms each provided with an upright, a pair of brackets carried by each upright and extending through the entrance slot into the corresponding channel,

rollers carried by said brackets in line with guided by said tracks, guide pulleys carried by said mast, a movable hoistingen-gine including a rotatable drum, a cable having its central portion wound on said drum and its ends fastened to said platforms, said cable passing over said guide pulleys, and a strut for fixing the hoisting engine at a predetermined distance from the foot Tl said mast to determine the normal lift of the apparatus.

10. An apparatus of the class described comprising a mast, tracks fastened to 0pposite sides of the mast, lifting platforms guided by said tracks, guide pulleys carried by said mast, a movable hoisting engine including a rotatable drum, a cable having its central portion wound on said drum and its ends fastened to said platforms, said cable passing over said guide pulleys, and a strut extending between the hoisting engine and the foot of the mast and adjustable in length to vary the normal lift of the apparatus.

11. An apparatus of the class described comprising a mast, tracks fastened to op posite sides of the mast, lifting platforms, guided by said tracks, guide pulleys carried by said mast, a movable hoisting engine including a rotatable drum, a cable having its central portion wound on said drum and mast to determine the normal lift of the apparatus.

In testimony whereof, I aflix my signature.

ROBERT M. ADAM. 

